Various types of apparatus are known which are designed for this kind of operation. Certain types have obtained greater acceptance than others. This invention provides improvements in some critical parts of an apparatus of one of said types which has been known since long ago. This type of apparatus comprises, in general, a water deaerating stage, a deaerated water and syrup mixing stage capable of accurately metering the syrup and water components of the mixture, and precarbonating stage in which a gas such as carbon dioxide is introduced in a current of said water-syrup mixture, and a final carbonating stage in which said mixture is saturated with the same or another gas, after which the mixture is refrigerated, settled and finally discharged from this stage as the final product.
The same applicant has already introduced important improvements in apparatus of this type. One such improvement comprises a special design of the mixing and metering stage which has been described, illustrated and claimed in U.S. Pat. No. 3,993,219 granted Nov. 23, 1976, to the same applicant of this invention.
The present invention provides still other improvements in this kind of apparatus which allows an even more considerable increase in the efficiency thereof; such other improvements have been described, illustrated and claimed in Argentine patent applications Ser. No. 265,361 filed on Nov. 5, 1976, and Ser. No. 268,889 filed on Aug. 22, 1977, by the same applicant of this invention.
The apparatus of the present invention comprises modifications which have in general the primary aim of obtaining the maximum possible division of the gas, such as carbon dioxide, into bubbles as small as possible so as to individually offer a maximum area of contact thereof with the liquid into which they must be diffused, and remain diffused. This allows the obtaining of a very uniform end product which has a high degree of homogeneity, and which has incorporated the maximum possible volume of gas for each definite type of end product.
This result is obtained intentionally creating turbulences and collisions between meeting streams at suitable different points along the path of the liquid from the precarbonating stage until its introduction into the final carbonating vessel, and specially by means of the novel and characteristic design of the precarbonating device, which allows the introduction of a gas such as carbon dioxide in the stream of syrup-water mixture, maintaining a constant ratio between the volume of the syrup-water mixture and the volume of the gas, and allowing also a considerably better intimate contact between the gas and the syrup-water mixture.
At other points along said path of the liquid streams there are intentionally produced additional turbulences and/or collisions between meeting streams (as the case may be). At one of such points a check valve of novel design is arranged, just before the entrance of the mixture to the final carbonating vessel, this valve acting not only as a check valve, but performing also the additional and simultaneous function of still more improving the mixing action and intimate contact between the liquid stream and the gas.
In the final carbonating vessel is also provided a device, based on the Venturi principle, which gives rise to a still better intimate contact between the syrup-water-gas mixture coming from the precarbonating stage, thus promoting a complete saturation of said mixture with additional gas which is introduced also in the final carbonating vessel.
These two features also form important aspects of the present invention.
A modulating valve of new design, controlling the rate-of-flow of the stream of liquid fed to the precarbonating stage according to the level of the liquid in the corresponding tank of the metering and mixing device of the apparatus, is provided between the output of the mixing and metering stage and the input to the precarbonating stage.
Another improvement provided by this invention is a deaerating device, based on the Venturi principle, which is arranged at the input of the deaerating vessel, which divides the entering water stream in many small jets so as to allow the vacuum pump to extract from the water any trace of air which could be present in it, thus improving to a high degree the efficiency of this stage, the function of which is to extract to the highest degree possible the air contained in the water.
Another new feature provided by the present invention is a new construction of the distributing tray of the final carbonating vessel which allows a thorough, quick and automatic cleaning and sanitation without it being necessary to disassemble the tray and its supporting structure.
Another improvement provided in the apparatus is an automatic washing arrangement associated with the tray distributing the product introduced into the final carbonating vessel.